1. Field of the Invention
This invention relates to a container structure, more specifically to an easy-opening top closure for a beverage container, especially for soda pop containers or beer containers.
2. Background Information
Previously, the conventional pop-top beverage container comprised a disposable tear tab that was detached from the top of the container creating an opening for the consumption of the contents of the container. The removable tear tabs typically had sharp or rough metal edges and when separated from the top closure member, created litter when it was dropped on the ground creating unsightly and potentially hazardous situations.
More recent containers having easy-open top closure members comprise rivet tabs which again typically have sharp or rough metal edges which are pushed or pried open with a finger so that the edge of the tab is forced downward and inward into the can. Further, with either of the above type designs, the can, once opened, cannot be partially closed.
U.S. Pat. No. 4,078,694 to Gnyp et al. ("the Gnyp patent") is directed to a container closure. The Gnyp patent discloses a container closure which includes a container end wall having an opening therethrough, a tab pivotably attached to the end wall, a hinge pivotably connecting the tab to the end wall and a sealing strip membrane beneath the tab to seal the opening. The Gnyp patent teaches that the sealing strip is designed to be ruptured by the tab with a pointed tip. The Gnyp patent also teaches that the sealing strip should be scored to assist in the tearing or rupturing of the sealing strip. These features increase the cost of manufacturing this design. Additionally, tearing of the sealing strip increases the likelihood of introducing debris into the interior of the container as a result of the tearing action.
U.S. Pat. No. 3,952,914 to Vogt ("the Vogt patent") is similar to the Gnyp patent above. The Vogt patent discloses a container closure which includes a container end wall having an opening therethrough and a separate rubber or plastic seal pivotably sealing the opening of the end wall. The Vogt patent teaches that the sealing member be a rubber or plastic piece which seals due to the beveled edge (i.e., a stopper effect). The Vogt patent also requires the pull tab extension 17 which adversely effects the cost-effectiveness of this design.